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Bump Metro to 0.88.0 - #59831
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Bump Metro to 0.88.0#59831
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## Summary: Bump Metro to 0.88.0, a breaking release: https://github.com/react/metro/releases/tag/v0.88.0 The changes React Native projects are most likely to notice: - Packages' `"exports"` are read from the package root, and `"browser"` redirections apply after them, so some subpath imports resolve to a different build. `resolver.unstable_resolveExportsFromPackageRoot` and `resolver.unstable_applyBrowserSpecAfterExports` turn either off. - `resolver.emptyModulePath` defaults to `metro:runtime/modules/empty-module`. Custom resolvers already have to delegate `metro:` specifiers they don't handle, for `metro:babel-runtime`, but code that reads the option as a file path breaks. - Lazy bundle URLs keep the file extension (`/src/Foo.js.bundle`). Old URLs still work. This also removes the defaults that Metro now has itself (`transformer.asyncRequireModulePath`, `transformer.allowOptionalDependencies` and `watchFolders: []`), and two Flow suppressions for transformer options that Metro's types now declare. Finally, `@react-native/metro-babel-transformer` passes `supportsInlineModules` to Babel in the caller, as `metro-babel-transformer` does, so that presets and plugins can tell whether `metro:inline` specifiers (react/metro#2037) will resolve. ## Changelog: [General] [Changed] - Bump Metro to 0.88.0 [General] [Added] - `@react-native/metro-babel-transformer` passes Metro's `supportsInlineModules` to Babel presets and plugins ## Test Plan: ``` yarn install --frozen-lockfile --ignore-scripts yarn flow-check yarn test packages/metro-config packages/react-native-babel-transformer packages/community-cli-plugin ``` New unit test for `supportsInlineModules`, which fails for `true` and `false` without the change. `getDefaultConfig()` returns the same values for every option with and without the removed defaults. Metro 0.88.0 was tested end to end in a React Native 0.89.0-rc.0 template app before release (react/metro#2192).
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Summary: Bump Metro to 0.88.0, a breaking release: https://github.com/react/metro/releases/tag/v0.88.0 Almost all of the breaking changes are integrator-facing, the others are resolver spec alignment. Users are most likely to notice: - Packages' `"exports"` are read from the package root, and `"browser"` redirections apply after them, so some subpath imports resolve to a different build. `resolver.unstable_resolveExportsFromPackageRoot` and `resolver.unstable_applyBrowserSpecAfterExports` turn either off. - `resolver.emptyModulePath` defaults to `metro:runtime/modules/empty-module`. Custom resolvers already have to delegate `metro:` specifiers they don't handle, for `metro:babel-runtime`, but code that reads the option as a file path breaks. **NOTE: *I intend to pick this to 0.89.0-rc.1*** ### Other changes in this PR - Removes the config defaults that now match Metro's core defaults (`transformer.asyncRequireModulePath`, `transformer.allowOptionalDependencies` and `watchFolders: []`) - Remove two Flow suppressions for transformer options that Metro's types now declare. - `react-native/metro-babel-transformer` passes `supportsInlineModules` to Babel in the caller, as `metro-babel-transformer` does, so that presets and plugins can tell whether `metro:inline` specifiers (#2037) will resolve. ## Changelog [General] [Changed] - Bump Metro to 0.88.0 [General] [Added] - `react-native/metro-babel-transformer` passes Metro's `supportsInlineModules` to Babel presets and plugins X-link: react/react-native#59831 Test Plan: ``` yarn install --frozen-lockfile --ignore-scripts yarn flow-check yarn test packages/metro-config packages/react-native-babel-transformer packages/community-cli-plugin ``` New unit test for `supportsInlineModules`, which fails for `true` and `false` without the change. `getDefaultConfig()` returns the same values for every option with and without the removed defaults. Metro 0.88.0 was tested end to end in a React Native 0.89.0-rc.0 template app before release (#2192). Reviewed By: vzaidman Differential Revision: D130252821 Pulled By: cortinico
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Summary:
Bump Metro to 0.88.0, a breaking release: https://github.com/react/metro/releases/tag/v0.88.0
Almost all of the breaking changes are integrator-facing, the others are resolver spec alignment. Users are most likely to notice:
"exports"are read from the package root, and"browser"redirections apply after them, so some subpath imports resolve to a different build.resolver.unstable_resolveExportsFromPackageRootandresolver.unstable_applyBrowserSpecAfterExportsturn either off.resolver.emptyModulePathdefaults tometro:runtime/modules/empty-module. Custom resolvers already have to delegatemetro:specifiers they don't handle, formetro:babel-runtime, but code that reads the option as a file path breaks.NOTE: I intend to pick this to 0.89.0-rc.1
Other changes in this PR
transformer.asyncRequireModulePath,transformer.allowOptionalDependenciesandwatchFolders: [])@react-native/metro-babel-transformerpassessupportsInlineModulesto Babel in the caller, asmetro-babel-transformerdoes, so that presets and plugins can tell whethermetro:inlinespecifiers (Resolver: Add metro:inline specifiers for importer-anchored inline modules metro#2037) will resolve.Changelog
[General] [Changed] - Bump Metro to 0.88.0
[General] [Added] -
@react-native/metro-babel-transformerpasses Metro'ssupportsInlineModulesto Babel presets and pluginsTest Plan
New unit test for
supportsInlineModules, which fails fortrueandfalsewithout the change.getDefaultConfig()returns the same values for every option with and without the removed defaults.Metro 0.88.0 was tested end to end in a React Native 0.89.0-rc.0 template app before release (react/metro#2192).